I would appreciate any help or pointers in helping me move from 4X5 to 8X10 macro work.

Up to now I've been doing close up work on small objects (1 to 2 inches tall) with my 4x5 and have been wondering what would it take to do this with a 8x10 camera, same objects but filling the 8x10 frame.

I have been using a Rodenstock 150 on a old 4X5 Arca Swiss mono rail camera. I typically max out the bellows in order to fill the frame but it works well for what I am trying to get.

My 8X10 is a bashed up, Burke & James mono rail and a 12" old brass lens and I cant get enough bellows for close up work, the closest I can get is about 5 feet. I expect to upgrade my 8X10 camera in the next few months, looking at the Sinar F series.

I have no idea what the formula might be for calculating what how much bellows one needs for a particular format and lens combination or if its even possible with the lens I have.

Eoghan